The invention was originally conceived and developed for use in the photographic arts. Subsequently, a myriad of other uses manifested themselves, as will become apparent as the description proceeds. Nevertheless, the initial development was directed to providing borderless easels for photographic work.
Easels have been used in the photographic art for many years. The purpose of the easels is to provide a surface for holding photographic prints or enlargements. "Borderless" refers to prints that do not have or do not require borders in the developed prints.
In the photographic art, many different steps are required to produce prints or enlargements. An early step is to expose photographic paper to allow an image to be placed on the paper. Another step is to locate the paper in the correct position to allow focusing of an enlarger, or an image producing device, on the desired location on the paper. Still another part of this process is to position all the different sized paper sheets to be used for the particular task on the easel. Also, the paper must be positioned accurately and securely to avoid distortion in the developed print. This entire process is typically performed in the dark to avoid overexposing a print or film, thereby destroying the latent image. In addition, many photographers personally incur all expenses because they work independently rather than for a company.
It is clear from the above description that many problems are associated with the process of developing prints. One problem is the cost of the time spent in all these steps. Another problem is the cost of expensive photographic easels that can position papers accurately and securely. Still another problem is completing the process in the dark, trying to handle equipment with many movable parts, making adjustments to the easel, as well as sorting out of the multiple sized paper for specific assignments.
In an attempt to overcome some of the problems mentioned above, the prior art has attempted to make improvements in a wide variety of easels. Many patents have been granted on easels. One of the best known is the De Brouwer U.S. Pat. No. 2,633,058. This patent teaches adjustable bars and other devices to hold down paper to prevent movement and to expose the paper all the way to its edges. Hess, in U.S. Pat. No. 4,155,644, attempts to make an improvement upon De Brouwer by using support pads for paper and a single bar to hold paper in a desired position. Yet these easels do not have provision for special blades to print borderless color or black and white prints. Some four bladed easels include a fixed scale to measure the width or length of the paper. Another such easel is Kostiner U.S. Pat. No. 4,190,357. This patent teaches the use of sliding scales for measuring paper size, plus masking blades which are removable. Petrini and Van Lue's U.S. Pat. No. 3,944,364 teaches a relatively simple easel using a paper support base with removable mask plates which tends to maximize the use of print paper. Still another attempt to improve on existing inventions is the use of vacuum easels, which eliminate the need for mechanical securing devices for the paper and are thus able to provide "borderless" prints. Nevertheless, a major disadvantage is the complexity and extremely high cost of a vacuum easel.
In summary, numerous problems exist with the prior art mentioned and others just as typical. Most, if not all, require adjustments, replacements of parts, masking, expensive fixtures, maintenance, time consuming steps to make adjustments, and easel space taken up by various securing devices and parts. Therefore flexibility in the choice of paper size is limited.
It is desirable to have a borderless easel which can be used with paper of different sizes, maximizes the easel space, minimizes the user's time, and is inexpensive to manufacture as well as maintain. Such an easel should be convenient, reliable, durable, easy to use, and, most importantly, hold paper in a desired location without damage or distortion to the paper.
Adhesives of various kinds and properties have been developed to secure one surface to another, such as paper products. Numerous inventions have been patented in attempts to optimize the adhesive properties of gels and sticks to permit affixing paper products together as in Cohen et al. U.S. Pat. No. 3,964,832. Bernard in U.S. Pat. No. 5,278,267 teaches an adhesive to affix corrugated board to other surfaces without peeling. Sakai in U.S. Pat. No. 5,190,820 teaches an adhesive which allows removal of paper products from another surface without tearing or leaving of an adhesive residue. Yet each of these patented inventions exhibit problems when considered in conjunction with a borderless easel. In many cases, the composition of the gel or adhesive is extremely complex in development, production, or in environmental requirements.
It is desirable to have an inexpensive, quick setting adhesive which allows a paper product to adhere to, yet be removable from an adhesive. Such an adhesive would be ideal for use with a borderless easel to allow paper prints to be held quickly and securely without the use of various devices, bars, masks, pins, weights or magnets.
Therefore, with all the noted problems, there is still a continuing need for a borderless easel using a pressure sensitive adhesive.